Story highlights Both Nevada Sen. Dean Heller and Arizona Sen. Jeff Flake decided to stick with Trump

The White House had suggested Trump was willing to work to defeat GOP incumbents

Washington (CNN) The two Senate Republicans in the most jeopardy of losing their seats in 2018 faced a choice in Tuesday's health care vote: Stick with President Donald Trump and face a barrage of Democratic attacks, or break ranks and risk a potentially serious primary challenge fueled by Trump himself.

Both Nevada Sen. Dean Heller and Arizona Sen. Jeff Flake decided to stick with Trump.

Their votes came after stern signals from the White House that the President was willing to work to defeat his own party's incumbents if they crossed him on health care.

Trump and White House aides have met and spoken with several potential Flake primary challengers.

And Trump, sitting next to Heller at a recent meeting, predicted the Nevada senator would reverse himself and vote to advance the GOP's health care effort Tuesday.

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