Some in the "tea party" movement would repal the 17th Amendment (direct election of senators). The Los Angeles Times disapproves:
Restoring the original political order to which many tea partyers seem to be drawn would require the repeal of more amendments than one.
For example, America was a different place before the adoption of the 14th Amendment, added after the Civil War. Like the 13th Amendment, which abolished slavery, and the 15th, which barred racial discrimination in voting, the 14th Amendment overrode what had once been seen as state prerogatives. It is best known for its definition of citizenship: "All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside." But it also profoundly altered the relationship between the states and the federal government.
The 14th Amendment also says: "No state shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any state deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws." And it gives Congress the power "to enforce, by appropriate legislation, the provisions of this article" (as it did in enacting civil rights legislation). If tea partyers want to restore the autonomy of the states, the 14th Amendment would have to go, along with the 17th.
Other amendments to the Constitution have expanded political participation, sometimes at the expense of state's rights. That was true not only of the 15th and 17th Amendments but also of the 19th, giving women the right to vote nationwide, and the 26th, granting 18-year-olds the franchise. The latter two amendments limited the states' ability to define qualifications for voting.
The Constitution is worthy of veneration, but many of its most admirable features didn't originate in the era of the three-cornered hats sported by some tea party activists. That includes the rights of the voters to choose — and remove — their senators
Berkeley law professor John Yoo takes a different view:
There’s a lot of truth to the argument that the enactment of the 17th Amendment undermined federalism. State legislatures have a greater institutional incentive to protect federalism than do the people of a state. The people of a state may want to expand federal program spending in order to get their share of tax revenues, even at the expense of greater national power over issues reserved to the states. Although they are also elected by the people, state legislators have more of an incentive to protect the original distribution of powers between the national and state governments.
Here is what James Madison had to say about the matter (during congressional discussion of the Bill of Rights in 1789):
[T]he State Legislatures will jealously and closely watch the operations of this Government, and be able to resist with more effect every assumption of power, than any other power on earth can do; and the greatest opponents to a Federal Government admit the State Legislatures to be sure guardians of the people’s liberty.
The 17th Amendment weakened the states’ ability to resist the expansion of federal powers. The problem is that there is no point to trying to fix this problem — an effort to amend the Constitution will be fruitless. It requires two-thirds of the Congress and three-quarters of the states. The Tea Partiers would be well advised to devote their efforts to achieving significant limits on the federal government — such as limiting federal spending, cutting taxes, and reversing Obamacare — that don’t demand an amendment to the Constitution. They will have a limited political window to apply their political capital; constitutional amendments will only waste it.