By ALAN FRAM, Associated Press

WASHINGTON (AP) — House Speaker Paul Ryan and Rep. Debbie Wasserman Schultz are about to test voters' anti-establishment mood, first hand.

In an election year in which supporters of both parties are seething against Washington, 15 states from Florida to Arizona have yet to vote in House primaries. They include challenges against Ryan, R-Wis., and Wasserman Schultz, D-Fla., who abruptly resigned last week as chair of the Democratic National Committee.

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Both seem likely to prevail, but surprises can happen in low-turnout summer primaries.

Here's a look at noteworthy contests, a prelude to a November election in which Democrats will make a long-shot bid to capture House control:

THE BACK STORY

Before this week, 31 states had held House primaries this year. Three incumbents lost, but none of their races supported the argument that voters want to throw the incumbents out — of the House, anyway.

Rep. Renee Ellmers fell to fellow North Carolina GOP Rep. George Holding, and Virginia Republican Rep. Randy Forbes also lost, both victims of court-ordered, redrawn district lines. Rep. Chaka Fattah, D-Pa., was defeated in April after indictment on federal corruption charges. He was later convicted and quit Congress.

THIS WEEK

Four states held House primaries Tuesday.

In the most striking election, Rep. Tim Huelskamp, R-Kan., a tea party lawmaker and persistent annoyance to GOP leaders, lost his bid for a fourth term.

Huelskamp's contest against Roger Marshall, an obstetrician, was unusual because GOP primary challengers usually accuse incumbents of being insufficiently conservative. Marshall argued that Huelskamp's rebelliousness got him kicked off the House Agriculture Committee, which is vital for western Kansas.

Their contest became a proxy battle between GOP conservatives and pragmatists. The anti-tax Club for Growth spent $400,000 to help Huelskamp, and members of the conservative House Freedom Caucus campaigned for him. The U.S. Chamber of Commerce and the Ending Spending Action Fund, which wants to curb federal expenditures, spent big dollars against him.

That prompted an angry response from Rep. Jim Jordan, R-Ohio, chairman of the Freedom Caucus, who on Wednesday called it an "an ugly and dishonest campaign" in which "Tim's record was attacked and misrepresented by big money special interest groups who wanted to exact their revenge."

RYAN'S RACE

Political novice Paul Nehlen wants to end Ryan's House career after nine terms, and he's getting help from Donald Trump. An unlikely defeat in the Aug. 9 primary would probably spell political doom for the GOP's 2012 vice presidential candidate and potential future presidential contender.

A tattooed, motorcycle-riding businessman, Nehlen labeled the speaker "Lyin' Ryan" on Twitter. He's attacked Ryan for favoring a Pacific trade deal and accuses him of being lax on immigration and beholden to the establishment.

Nehlen got a boost from Trump when the GOP presidential candidate said in a Tuesday interview with The Washington Post that he is "not quite there yet" in endorsing Ryan. That could be payback for Ryan saying in May that he was "just not ready" to back Trump. Ryan subsequently endorsed Trump but has criticized him frequently, and their relationship is cool.

Trump praised Nehlen this week for defending his criticism of the Muslim parents of an American soldier slain in Iraq.

Ryan campaign spokesman Zack Roday expressed confidence in a primary victory and said, "Neither Speaker Ryan nor anyone on his team has ever asked for Donald Trump's endorsement."

Ryan has raised 12 times the $489,000 Nehlen has reported collecting. Not taking chances, Ryan is airing his third TV ad, with people waving flags and praying as Ryan tells the camera, "I am committed to securing our borders."

WASSERMAN SCHULTZ'S TRAVAILS

Vermont Sen. Bernie Sanders complained that Wasserman Schultz's DNC, which historically has remained neutral in presidential primary season, backed his victorious Democratic presidential rival, Hillary Clinton. Wasserman Schultz abandoned her party post as last week's Democratic convention began after leaked emails revealed party staffers had done just what Sanders had suspected.

That has turned Wasserman Schultz's focus to her Aug. 30 primary, where she's opposed by upstart law professor Tim Canova. He's backed by Sanders and has mimicked Sanders' populist style by raising huge sums from small individual contributions. That has let Canova stay surprisingly competitive financially, raising $2.3 million compared to Wasserman Schultz's $3.1 million.

Yet the Miami-area district favored Clinton over Sanders by 2-1 in March's presidential primary. And Wasserman Schultz, seeking a seventh House term, gets high marks for paying attention back home.

ALSO IN FLORIDA

About half of Florida's 27 districts feature competitive primaries, including seven in which incumbents are stepping down or running for the Senate:

—Republican Rep. Jeff Miller is leaving a Panhandle seat so conservative that one leading competitor, State Sen. Greg Evers, raffled off an AR-15 rifle among people who "liked" his Facebook page. Another, State Rep. Matt Gaetz, backed a local sheriff who called the Black Lives Matter group "a terrorist organization."

—Democratic Rep. Corrine Brown, indicted on federal fraud charges, faces strong competition in north Florida.

—GOP Rep. Dan Webster, who unsuccessfully challenged Rep. John Boehner for the House speakership in 2015, is seeking a different open seat after his district became more Democratic.

OTHER NOTABLE PRIMARIES

—Liz Cheney, daughter of former Vice President Dick Cheney, is a favorite GOP contender for Wyoming's open, lone House seat Aug. 16.

—An Aug. 30 fight among Republicans for the northern Arizona seat of Democratic Rep. Ann Kirkpatrick, who's challenging GOP Sen. John McCain.