Control of the big three — the governor’s office, the State Senate, and the State House of Representatives — is up for grabs in November.

With control comes the power to set the state political agenda.

Today, we look at the Senate. The democrats hold a 27-22 majority, but as we saw from last year’s budget battle when three Democrats aligned themselves with minority Republicans to pass a budget, that hold has been tenuous.

The battle to get the 25 votes to control the budget was so intense that Republicans, even with a likely lawsuit from Senate staff, let Sen. Pam Roach back into the caucus to ensure her vote. Two of the three Democrats, Rodney Tom from Bellevue and Tim Sheldon from Potlatch, voted with Republicans on the budget and will be back next session. Democratic leaders are working hard to try and increase their majority so they won’t have to worry about defections. Republicans believe they may have a chance to win outright control.

The third Democrat to side with the Republicans was Sen. Jim Kastama from the 25th District in Puyallup, who ran for Secretary of State and lost in the primary. However, his seat will almost certainly be won by Republican Rep. Bruce Dammeier.

Sen. Joe Zarelli, a key player for the Republicans, isn’t running again, but his seat appears safely in the Republican column. The other major player stepping down is Democratic Majority leader Lisa Brown in Spokane, but it appears the position will stay in Democratic hands.

The 5th District, currently held by Republican Sen. Cheryl Pflug, may be different. Pflug resigned to take an appointment to the Growth Management Board. She endorsed the Democratic nominee Mark Mullet over Republican Brad Toft. Mullet took 52 percent of the primary vote to Toft’s 48 percent.

Republicans are not happy with Pflug, but in a close race, the nod likely goes to Mullet.

Democratic Sen. Rosemary McAuliff, in the 1st District, was thought by many to be in trouble and may yet be. She polled 44 percent to Republican Dawn McCravey’s 42 percent. However, a second Democrat captured over 13 percent, which increases Democrats’ optimism that McAuliff is likely to hold on. They’re probably right, but it could be very close.

The same scenario is also evident in the 2nd District as Republican Sen. Randi Becker was thought to be vulnerable and was in a virtual tie with her Democratic opponent at about 40.6 percent each. However, a second Republican took almost 20 percent of the vote that will likely go to Becker in November.

Down in Vancouver, Republican Sen. Don Benton is leading Democratic State Rep. Tim Probst, 52 percent to 48 percent. Both sides believe they will win this seat. History favors the incumbent, Benton, but if you spend time at the race track and like to bet on long shots pulling an upset, this might be it.

The most closely watched race in the Senate is the 10th District up in the Oak Harbor area, where longtime Olympia power Democrat Mary Margaret Haugen polled only 47 percent and was trailing Republican State Rep. Barbara Bailey, who had 53 percent. They were very close on election night, but Bailey got a bump in late arriving ballots.

Haugen is chair of the transportation committee and has helped push many projects that benefit her area. She also stirred up her conservative leaning constituents by voting in favor of marriage equality.

Haugen has raised more money than Bailey by almost 2-1, but after both sides analyze the results, they will start putting big money into this race.

Here again, leaders from both parties believe their candidate will win. It is a conservative district and both House members are Republican, as is the likely winner to replace Bailey. Conventional wisdom leans toward Bailey in a big upset.

Under the most optimistic Democratic projection, it could be 28-21 Democratic. Under the most optimistic Republican scenario, they would gain control 25-24 or be down only 25-24. While possible, neither appears likely. Most likely? Democrats retain control 26-23 — and hope they can keep their caucus all on the same page.

But keeping everyone in the caucus together will be problematic for Democrats if they don’t get at least 27 votes. Fewer than 27 Democratic votes puts Senators Rodney Tom and Tim Sheldon in play on the Republican side, creating several potential issues.

If King County Councilman Bob Ferguson is elected Attorney General, his council seat could go to a Democratic member of the Legislature. But that won’t play in to this scenario as Democrats control all the positions. However, if Reagan Dunn is elected Attorney General, the dominoes could change the seating in the House of Representatives. Democratic Rep. Pat Sullivan would be the most likely choice.

Lastly, the reason that Democrats really want 28 votes is Democratic Sen. Derek Kilmer is likely to be elected to Congress from the 6th District and his seat in the Senate would be in play in 2013.

You never know what will happen in an election. Voters always get the last word.

Next week, we’ll look at the House of Representatives.