(CNN) The National Defense Authorization Act is a massive $696 billion defense policy bill that covers everything from F-35 fighter jets to Guantanamo Bay to military pay raises.

It's also a prime opportunity for Democrats to try to force politically difficult votes on Republicans dealing with President Donald Trump's business ties, his family members in the administration and his relationship with Russia.

Lawmakers have submitted more than 400 amendments to the defense spending bill that the House is debating this week, as it's one of the few so-called "must-pass" measures still around in Congress. The bill has been signed into law now for 55 straight years.

The legislation always attracts hundreds of amendments because it covers a wide swath of policy, and it's the first major national security bill of the Trump administration where Democrats can use amendments to try to pin down Republicans on Trump.

There are proposed amendments to review the security clearances of Trump family members, to require reports on the cost of presidential travel to Trump proprieties, and to prevent the Pentagon from spending money on hotel rooms at Trump properties.

There are also a host of amendments dealing with Russia and election hacking, cybersecurity sharing and Syria.

"Just like the revelations that came up today, we need to have more oversight and more answers coming from the Trump administration in terms of their relationship with Russia, not less — and this is a good opportunity," Rep. Ruben Gallego, an Arizona Democrat with several amendments pending, told CNN. "To the extent to where we can have oversight we're going to take it, in my opinion, and that's why I've introduced these types of amendments."

Avoiding difficult votes

Of course, few -- if any -- of the amendments directly dealing with the President are likely to get a vote on the House floor, as the Republican-led House Rules Committee decides which amendments are "in order" for votes and which get tossed out.

The House rules committee made the first batch of 85 amendments in order Tuesday evening, with only a couple dealing with Russia, and none of the amendments tied to Trump's businesses. The panel will consider final amendments to allow for floor votes on Wednesday evening.

House armed services committee Chairman Mac Thornberry argued that amendments dealing with Trump's business interests did not belong in the defense policy bill.

"I don't think they're really relevant to our bill and I would just as soon keep our bill focused on the troops and national security," the Texas Republican told CNN.

But Democrats argue that the House is using procedural tactics to defend their members from tough votes. The rules panel also included a procedural trick to strip language that was approved by voice vote during committee markup of the bill to prevent the Pentagon from paying for a border wall.

The amendment to remove the border wall provision is "considered as adopted" when the overall rule allowing debate is passed, averting a specific vote on the wall provision.

The fight over amendments is nothing new, of course. Just as Democrats were able to block Republican amendments during the first two years of the Obama administration, many of the Democratic amendments -- and some prickly Republican ones -- are tossed out of the NDAA every year.

But Rep. Adam Smith of Washington, the top Democrat on the panel, argued things are different this year, even if he predicted the Trump amendments would not get votes.

"Obama wasn't all tied up with the Russians and making money off the Defense Department and making money from foreign governments," Smith said. "Obama certainly doesn't have a son, but he has a daughter who wasn't meeting with Kremlin operatives to get after the Clinton campaign, so we have a slightly different situation."

Trump hotels, security clearances and more

Still, with or without votes, the NDAA amendments give House Democrats a legislative avenue to try to pressure Republicans, and they provide insight as to where Democrats will focus when it comes to Trump heading into the midterms.

Gallego, a Marine Corps veteran on the armed services committee proposed several of the Trump-related amendments. One would require the Office of Government Ethics to review security clearance applications from the President's family members "to determine whether they have substantial commercial relationships with foreign enterprises or financial institutions."

Democrats also focused on the President's travel -- and his network of hotel properties.

An amendment from Rep. Ted Lieu of California would prevent the Pentagon from spending money to purchase hotel rooms or conference space "with any entity owned by or significantly controlled by the President or a member of the President's immediate family, including any such entity held in trust."

Another proposal from Rep. Tom O'Halleran of Arizona, co-sponsored by North Carolina Republican Rep. Walter Jones, would require reports to the Pentagon every 90 days on the cost of presidential travel, including the specific costs for travel to Trump-owned properties.

Trump's meeting last week with Vladimir Putin -- and his subsequent tweets about a cyber working group -- provided a chance for amendments to respond to the news cycle in real time, as three Democrats proposed amendments Monday to block cybersecurity sharing efforts with Russia.

Two Russia related amendments were approved for floor debate: One from Rep. Dwight Evans of Pennsylvania to require a report on any US-Russian cooperation agreement in Syria, and from Rep. Lou Correa of California for a report on Russia's cyberattacks against the Pentagon.

The contentious amendments aren't limited to Trump, either, with proposals ranging from a new war authorization against ISIS to blocking Turkey from obtaining F-35s until it cooperates with the investigation into the May violence outside its US embassy.

Debate on the defense begins on the House floor Wednesday, with amendments being considered for the rest of the week.