Washington (CNN) For months, Nevada and North Dakota were among the biggest headaches facing President Donald Trump and Senate Republicans headed into November's midterm elections.

In Nevada, until March, the GOP had two well-known candidates. In North Dakota, until February, it had none.

But after aggressive intervention from the White House, Trump's political team and Senate Majority Leader Mitch McConnell, the GOP now has one candidate in each of those races -- giving the party nothing to worry about in Tuesday's primaries in two of the most important Senate battlegrounds on the 2018 midterm map.

"This is an example of what it looks like when things work well," said Josh Holmes, a top political adviser to McConnell. "Both of them had opportunity to be big trouble."

In North Dakota, despite a lobbying effort that included a visit with Trump at the White House, Rep. Kevin Cramer decided in January against a Senate run.

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