U.S. Rep. Allyson Schwartz, candidate for the Democratic gubernatorial nomination in Pennsylvania steps from the booth after voting Tuesday, May 20, 2014, in Jenkintown, Pa.
Matt Rourke/AP

Tuesday primaries: What to watch as voters head to the polls

Updated

Voters in six states went to the polls Tuesday to cast ballots in primary races that are critical for setting match-ups for the November midterms. Several of the contests are also being seen as a test of the Republican Party’s clout against tea party –backed candidates.

The highest-profile races are in Kentucky and Georgia. In the Bluegrass State, Senate Minority Leader Mitch McConnell successfully fended off a primary challenge from tea party favorite Matt Bevin. McConnell will face Democratic Secretary of State Alison Lundergan Grimes in November’s general election

The Daily Rundown, 5/20/14, 11:07 AM ET

2014 midterms defined by battle for Senate

Chuck Todd goes over the two speed bumps Republicans may run into in the battle to re-take the Senate this midterm: Georgia and Kentucky.

And in Georgia, a crowded seven-candidate Republican primary will determine two spots for a likely run-off primary in July, as no one person is expected to break the 50% threshold required to seal the nomination. That nominee will likely take on frontrunner Democrat Michelle Nunn.

But other primaries are definitely worth keeping an eye on too. Here’s what to look out for:

Pennsylvania

Voters in the Keystone State decided businessman and former state revenue secretary Tom Wolf is the Democrat to take on Republican Gov. Tom Corbett. The governor was elected in the tea party wave of 2010 but is now considered vulnerable and unpopular.

Wolf – who spent more than $6 million of his own money on his bid – beat out three other candidates, including better-known competitors U.S. Rep. Allyson Schwartz and state Treasurer Rob McCord.

As expected, Corbett – who was running unopposed – won the gubernatorial GOP primary.

Bill and Hillary Clinton’s star power will be tested in the Keystone state as well. The couple has been stumping for their daughter’s mother-in-law, Marjorie Margolies, who is trying to win back her old House seat representing the Philadelphia suburbs (which is Schwartz’ old district). There hasn’t been any recent polling in the reliably-blue district, so it’s difficult to predict what will happen.  Margolies is up against three other candidates, including state Rep. Brendan Boyle, state Sen. Daylin Leach and Dr. Val Arkoosh.

Oregon

The Republican Senate primary is getting some last minute attention after news broke that frontrunner Monica Wehby – endorsed by the GOP establishment – was accused of “stalking” her ex-boyfriend last year. Wehby is up against state Rep. Jason Conger. The winner will take on first-term Democratic Sen. Jeff Merkley  – who some Republicans think could be vulnerable – in the November election. Abortion has been a key issue in the race. Wehby, a pediatric neurosurgeon, has said she’s pro-life but says the procedure should not be in the hands of the federal government. Conger is a strict social conservative and opposes both abortion and gay marriage. Former Republican presidential nominee Mitt Romney endorsed Wehby while strict social conservative and former Pennsylvania Sen. Rick Santorum backed Conger.

Idaho

The highest profile race here is for the House seat currently occupied by eight-term Rep. Mike Simpson, who is facing a tea party-backed attorney, Bryan Smith. While Smith received early backing from groups like the Senate Conservatives Fund and the Club for Growth, Simpson has received substantial money – outraising Smith overall – with help from the U.S. Chamber of Commerce.

Arkansas

The important races here will set the stage for the general election.

When it comes to the governor’s race, former congressman Asa Hutchinson is expected to clinch the nomination for the Republicans while former congressman Mike Ross is expected to win for the Democrats. The GOP views the state as a prime pick up to replace outgoing Democratic Gov. Mike Beebe.

For the Senate race, Democratic Sen. Mark Pryor and GOP opponent Tom Cotton, as expected, won their respective nomination, according to the Associated Press. Pryor is considered one of the most vulnerable Democratic incumbents running for re-election this year.

Hardball with Chris Matthews, 5/19/14, 7:50 PM ET

Democrats hope for gains on Super Tuesday

Chris Matthews talks with David Corn and Ken Vogel about Tuesday night’s big primary races in Georgia, Pennsylvania and Kentucky. Do Democrats have a shot at picking up Senate seats?

Arkansas, Georgia, Idaho, Kentucky, Oregon, Pennsylvania and Senate

Tuesday primaries: What to watch as voters head to the polls

Updated