WASHINGTON (AP) — Republican congressional candidates are increasingly seeking voters' support by saying they will check the agenda of a President Hillary Clinton.

The tactic's use is spreading as the GOP worries that presidential candidate Donald Trump's poor showing in polls could translate to not capturing the White House and helping Democrats capture a Senate majority and erode GOP House control.

In one new fundraising email, House Speaker Paul Ryan's political operation seeks money for Republican congressional candidates by calling the appeal "our very last chance" to stop Clinton and House Democratic leader Nancy Pelosi. The solicitation was sent over the signature of former House Speaker Newt Gingrich.

Republican congressional candidates and their supporters are employing television ads to make a similar argument in Indiana, Missouri, Michigan, California and elsewhere.

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