Republicans appear to be shoring up their hold on the Senate with just over two weeks to go before the midterm elections.

Late last week, election watchers put North Dakota's Senate race in the "lean Republican" category, giving the GOP an extra boost that should make it easier for it to keep control of the Senate.

The shift against Sen. Heidi Heitkamp, D-N.D., came just days after her campaign apologized for outing women who are victims of sexual assault. But it was always a close race, and many predicted Rep. Kevin Cramer, R-N.D., was in a good position to win her seat.

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The race shift has a big impact on expectations for Election Day. Republicans now hold 51 seats, and now seem likely to pick up a seat or two on Election Day.

"Today, a Republican net gain of a seat or two seems most likely, moving the GOP up to either 52 or 53 seats, though a gain of three seats or no net change are entirely possible," Charlie Cook of the Cook Political Report late last week.

Democrats are defending 26 seats this year, and Heitkamp's is the only race that now leans Republican, while four other races are tossups.

Republicans, in contrast, are only defending nine seats, though four of them are tossups as well.

Heitkamp also boosted the GOP's chances as measured by 270towin. That group's latest Senate map says the GOP will likely win 50 seats and have a shot at six tossups, after saying last week the GOP would win 49 seats and then battle for seven tossups.

FiveThirtyEight also sees 50 Republican wins with just one tossup race, although that site has eight Democratic seats that are likely or leaning Democrat, and just four GOP seats in those categories.

Poll watchers still have the House turning Democrat, but seemed to cool over the last week on the question of how many seats Democrats might win.

The Cook Political Report puts Democratic gains at between 25 and 35 — they need just 23 to win control of the House.

270towin says Democrats only need to win a third of tossups to control the House, and FiveThirtyEight says on average, Democrats should win 40 seats or so.