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A new effort is under way in Congress to legalize marijuana.

After Colorado and Washington became the first two states to approve the sale and use of pot, marijuana advocates are turning their eye toward the federal government - something they don't often do.

Members of Congress will introduce between eight and 10 bills to roll back federal marijuana restrictions and levy new taxes.

The first two were introduced this week by two liberal members of Congress. Reps. Jared Polis, D-Colo., and Earl Blumenauer, D-Ore., on Monday rolled out a pair of bills that would legalize and tax marijuana at the federal level, while still allowing states to ban it.

Polis's bill, the Ending Federal Marijuana Prohibition Act, would remove marijuana from the list of banned substances under the Controlled Substances Act and regulate pot under a renamed Bureau of Alcohol, Tobacco, Marijuana and Firearms. Marijuana growers would have to buy permits to offset the costs of federal oversight.

Blumenauer's bill, the Marijuana Tax Equity Act, would levy a 50-percent excise tax on the first sale of marijuana, typically from growers to processors or sellers, plus annual "occupation taxes" of $1,000 and $500 on marijuana growers and anyone else engaged in the business.

Rep. Dana Rohrabacher, R-Calif., meanwhile, plans to introduce another marijuana bill sometime soon. He's the only Republican to formally support either Polis or Blumenauer as a cosponsor.

Blumenauer's office confirmed that a slew of bills are on the way.

"We are in the process of a dramatic shift in the marijuana policy landscape," Blumenauer said in a prepared statement on Monday.

He may be right. Marijuana legalizers enjoyed unprecedented success in 2012, hitting on their two major legalization initiatives at the state level in Colorado and Washington. Since then, bills have been introduced to roll back marijuana restrictions in Hawaii, Oklahoma and Rhode Island.

It's unlikely Congress will legalize pot anytime soon, despite polls showing broader public acceptance of pot. In December, 64 percent of Gallup respondents said they don't want the federal government stepping in to prevent pot legalization in states that allow it. In November, another nationwide Gallup poll showed that 48 percent think marijuana should be legal, while 50 percent think it shouldn't be.

But Polis's bill only has 11 cosponsors and must make its way through the Republican-controlled House Agriculture Committee. Blumenauer's has two and must make its way through the GOP-controlled House Ways and Means Committee.

What's significant about the new push, however, is that it comes on the heels of actual state-level policy change. State and federal laws now thoroughly conflict on the topic of marijuana, and never before has Congress considered legalization in that context.

In fact, Congress rarely considers marijuana legalization at all. The Washington, D.C.-based Marijuana Policy Project considers a 2011 effort by then-Reps. Barney Frank, D-Mass., and Ron Paul, R-Texas, to have been the first serious effort to end marijuana "prohibition" at the federal level. That bill went nowhere. Before that, Frank pushed a bill in 2008 that mostly decriminalized marijuana federally. In a Democratic Congress, that bill died in committee. One of its seven cosponsors signed on by accident.

The present effort appears more coordinated. Along with their bills, Polis and Blumenauer released a 20-page white paper on the history of marijuana's illegality. It's the first time pot legislation has been introduced in such a multi-bill wave.

For decades, marijuana advocates have pushed medical-pot laws and decriminalization measures through state ballot initiatives and state legislatures. The federal push, unlikely as it may be, represents a new prong in their strategy.