Most political eyeballs are understandably transfixed on the presidential race. But there is much drama brewing in the race for the Senate. And while the unhinged Republican presidential primary may give an impression of a nation gone mad, the way vulnerable Republican Senate incumbents are struggling to hold on to their seats is a reminder that the nation is not in a right-wing mood.
The Senate is within reach for the Democrats in 2016. They need to net four seats (five if they lost the White House, but doubtful they would net five seats while losing the White House). As of today, six Republican-held seats (and one Democrat-held seat) are deemed "toss-ups."
All the incumbent Republicans in the toss-up states are first-termers representing blue states who were elected the Tea Party-infused 2010 midterm. They've never won statewide in a presidential election year where Democratic turnout is expected to rise.
How are Democrats doing in those races? And how are Republicans strategizing to save their seats?
ILLINOIS: Sen. Mark Kirk vs. Rep. Tammy Duckworth
Kirk's campaign released to the media an internal poll showing the incumbent behind by three points. Campaigns only release internal polls when they make their candidate look good, so it's a sign of weakness to release one that shows the candidate behind.
Kirk is arguably the most moderate Republican senator next to Maine's Susan Collins, and he is looking to trade on that reputation in order to survive November.
He is one of the few Republicans that has met with Supreme Court nominee Merrick Garland, called for an up-or-down vote, and has gone as far as saying, "I would consider voting for him." A supporter of equal marriage rights, he even secured the endorsement of the Human Rights Campaign.
His first attack ad after the Illinois primary was not accusing Duckworth of being "liberal" but of being "partisan," stressing that she votes with her party "94 percent of the time." Such attacks were sufficient for Republicans in 2014 to oust red-state Democrats, but it's far less clear this will be a potent line of attack in Illinois.
NEW HAMPSHIRE: Sen. Kelly Ayotte vs. Gov. Maggie Hassan
This is a genuinely close race, with the incumbent Republican senator running against the incumbent governor. Ayotte is ahead in all polls taken this year, with an average lead of 4.5 points.
Ayotte notably tacked left last fall to embrace President Obama's Environmental Protection Agency regulations to cut carbon emissions, and touting her support in an ad.
But she may have a right-wing primary challenger to worry about. The Senate primary is not until September, and the filing deadline is in June. New Hampshire conservatives don't all trust Ayotte, so if she drifts too far left, she may attract serious opposition. (Already, she has one challenger, though he is not a doctrinaire conservative.)
In turn, she has not been as warm to Garland as Kirk. She initially said she would not meet with him, then changed her mind under pressure, while still insisting that she not does support a vote on the nomination before the election.
She also has to navigate the strong support for Donald Trump among her state's Republican voters. She said she would support Trump if he was the nominee.
Gov. Hassan is a popular governor, with a 51 percent approval rating versus 30 percent disapproval, in a poll last month. But in recent days she has been tripped up by a scandal involving a sexually abusive teacher at the high school where her husband was the principal.
OHIO: Sen. Rob Portman vs. former Gov. Ted Strickland
Strickland was booted out of office at the same time Portman was elected in the Tea Party year of 2010, as Strickland suffered the blame for the economic consequences of the 2008 market crash. But he holds a sight edge over Portman in the two polls that have been taken this year.
Portman is weighed down by his long-standing association with free trade agreements, having been the U.S. trade representative in the Bush Administration. A Democratic PAC ad hits Portman on voting for NAFTA and for permanent normal trade relations for China while in the U.S. House, then negotiating CAFTA as Bush's trade representative. Portman is trying to mask that record by opposing the Trans-Pacific Partnership.
While Democrats accuse Portman of sending Ohio jobs overseas, Republican ads attack Strickland for the job losses on his watch as governor.
Portman is following the same line as Ayotte on the Garland nomination, at least for now: agreeing to meet with Garland while still opposing formal hearings and a vote. But unlike Ayotte, Portman is past the Ohio Senate primary.
WISCONSIN: Sen. Ron Johnson vs. former Sen. Russ Feingold
Feingold's return to the Senate seems like a near-lock, as Johnson is a fervent right-winger with little capacity or inclination to bow to his state's blue tint. For months Feingold was topping Johnson by double digits in polls. In late March, two polls showed the margin shrinking to less than five. But an April poll from Loras College shows a nine-point spread.
Johnson, a CEO before becoming a senator, voted for fast-track trade negotiation authority, but has yet to take a position on the Trans-Pacific Partnership. Feingold is pressing Johnson to pick a side. Johnson has also refused to meet with Garland.
PENNSYLVANIA: Sen. Pat Toomey vs. TBD
Pennsylvania may be the toughest toss-up for Democrats to snatch. In the most recent poll, Toomey holds an eight-to-nine-point lead, depending on who Democrats nominate in the April 26 primary.
And Toomey is leaning leftward in hopes of winning the state's moderate, suburban vote. A new ad makes the most of his failed attempt at passing legislation to expand gun background checks, featuring an endorsement from a leading Pennsylvania gun control activist, and Toomey talking with moms on a playground.
But Toomey's tack left doesn't apply to African-American voters concerned about excessively violent police tactics. Another ad offers that "when rioters destroyed American cities, Pat Toomey stood strong with police ... and denounced the riots when others wouldn't."
Polls could change once Democrats settle on a nominee. Most expect the nominee to be either former Rep. Joe Sestak or former gubernatorial chief of staff Katie McGinty.
McGinty has considerable Democratic establishment support, including President Obama. Sestak was a progressive favorite in 2010 when he defeated Sen. Arlen Specter in the Democratic Senate primary, but McGinty is attacking him from the left because he has spoken positively of the Simpson-Bowles deficit reduction plan. (He insists he does not agree with the plan's Social Security and Medicare cuts.)
A third candidate, Braddock Mayor John Fetterman, is running as a plain-spoken, blue-collar Bernie Sanders-supporting progressive, but has yet to register strong poll numbers.
FLORIDA: TBD vs. TBD
Marco Rubio is leaving this seat open and it is far from clear who will be nominated in either party. The primary is not until August 30.
The Democratic primary pits the brash progressive Rep. Alan Grayson against former Republican-turned Democrat Rep. Patrick Murphy. President Obama has entered into this race as well, endorsing Murphy. But many Florida progressives criticize Murphy's flirtations with Social Security reform, support for the Keystone pipeline and Wall Street campaign contributions.
The Republican field is crowded, and a recent poll had no candidate breaking 12 percent.
NEVADA: TBD vs. TBD
Harry Reid is retiring and whether Republicans can make a run at the seat depends on who wins the June 14 primary.
Rep. Joe Heck has long been considered the frontrunner for the nomination, and he has been cognizant of the state's Latino vote. He has supported legalization of undocumented immigrants, although he opposed the 2013 bipartisan Senate immigration reform bill.
But Sharron Angle, the right-wing 2010 nominee who ran a disastrous campaign against Reid, recently jumped in the race. If she won the nomination again, the seat will almost surely remain blue. Angle could also force Heck to hew right to survive the primary, thereby compromising his general election prospects.
A February poll showed Heck edging the likely Democratic nominee, former state attorney general Catherine Cortez Masto, by three points. But Angle loses by 13.