Washington, Colorado, Alaska Senate races: When will we know who won?

As Tuesday night drew on toward Wednesday morning, three US Senate races – Colorado, Washington State, and Alaska – remained way too close to call.

Will they be determined before the sun goes down again? Not necessarily. Recounts loom in at least two states, which could last weeks, and both parties are lawyered up for the legal battles that might ensue.

These three nail-biters won't determine which party controls the Senate. With outcomes elsewhere already known, Democrats will remain the majority party there, although by a slimmer margin. But just how slim remains to be seen, and on a night when Democrats took the worst midterm shellacking in the House of Representatives since 1946, they're hoping for just a bit of good news.

Here's where things stand:

Colorado. Democratic Sen. Michael Bennet and Republican Ken Buck are within just a few thousand votes of each other, with more than 1.4 million ballots tallied and thousands of provisional and write-in ballots yet to be counted.

If the margin remains this slim, state law calls for an automatic recount, which wouldn't take place until after Thanksgiving. At time of writing, Mr. Bennet was leading by less than 9,000 votes.

Colorado will get a new elected senator in any case. Bennet was appointed to the seat last year when Ken Salazar left to become Interior secretary in the Obama administration. Buck is a state prosecutor and is favored by the tea party.

According to the watchdog group Sunlight Foundation, the contest drew more outside money (nearly $33 million) than any other Senate race.

Washington State. The race here is extremely close as well. Three-term Democratic incumbent Patty Murray is battling it out with Republican challenger Dino Rossi. At the moment, they are separated by no more than one percentage point.

Since mail-in ballots can be postmarked as late as midnight on Election Day, thousands of ballots may not reach election officials until later this week. The key question is, which part of the state will they come from? If a large portion are from King County (Seattle), that favors Ms. Murray. If they are from more suburban and rural counties, or from Republican-majority Spokane, that could help Mr. Rossi.

Washington State has recent experience with long, drawn-out recount fights.

Rossi has twice run for governor and lost. In 2004, he lost by just 129 votes to Gov. Christine Gregoire (D) – but only after a second hand recount that was settled months later by the state Supreme Court. It was the closest gubernatorial election in US history.

Alaska. This one's really unusual.

After being defeated in the Republican primary by tea party favorite Joe Miller, incumbent Sen. Lisa Murkowski decided to run as a write-in candidate against Mr. Miller and Democrat Scott McAdams.

At this point, write-in candidates have won 40 percent of the vote. Miller has 35 percent, and Mr. McAdams has 24 percent.

It's probably correct to assume that most of those write-ins are for Senator Murkowski. But it's not a sure thing because dozens of other names are on the official list of write-in candidates made available to voters at polling places around the state.

Then there are the mail-in ballots yet to arrive. Officials won't begin counting those – or even reading the write-in ballots – until the week after next. If Murkowski pulls it off, she'll be the first to do so since Strom Thurmond in 1954.