Republicans need to gain six seats to win the Senate, and while a complete sweep of races now in play would give them a net pick-up of 10, their majority is most likely to be narrow.

That reality could quickly temper the jubilation for conservatives who have long dreamt of ousting Harry Reid from the majority leader’s perch and confronting President Obama on equal footing during his last two years in office.

It would also present party leaders with a critical–and immediate–choice.

“One of the first things Speaker Boehner and Senator McConnell will have to do is sit down and decide how much they want to legislate and compromise versus how much they want to use the floor of the House and Senate to protect their presidential candidates,” said Jim Manley, a Democratic strategist and former Reid adviser.